Television has become the world's predominant communications medium. The variety of programming available on television has mushroomed in recent years with the growth of cable networks. In many areas, a viewer can select programming from among dozens of channels, broadcasting news, talk shows, movies, soap operas, serials, etc., from Geraldo Rivera to William F. Buckley, from the banal to the sublime (or the reverse, depending on one's point of view).
Although a large amount of information is broadcast via television, the capability to selectively view television is primitive. Published television listings typically contain a minimal amount of information about the program to be shown, are often difficult to understand, and are subject to frequent errors and changes. Furthermore, a certain amount of television programming, such as a news broadcast, by its nature can not be described in advance.
Most viewers would like greater control over what is being viewed. They may, for example, wish to view specific portions of a news program or a talk show dealing with a topic of interest. They may wish to monitor multiple channels simultaneously. They may wish to screen out programming they regard as offensive.
In theory, a viewer would record one or more television signals on one or more recording devices, such as commonly available video cassette recorders (VCRs), and review all recorded signals, editing such portions as desired. In reality, this would be an extremely tedious and time consuming task.
There has been some recognition of a need to provide a viewer with greater control over what is being watched. For example, it is known in the art to place a small window in one corner of the television display, in which is shown the video signal of another broadcast channel, enabling the viewer to screen one channel while simultaneously watching another. As helpful as this feature is to the viewer, it is obviously limited in its capabilities. Screening multiple channels would require a separate window for each one. The screening must be done at the time the signal is broadcast. If something of interest is detected, the channel must be switched, possibly foregoing programming of interest on the channel first being viewed.
Television viewers have accepted this lack of ability to screen, preview or extract portions of television programming only because no alternative has been presented. However, a need exists for advanced capability on the part of the viewer to selectively control what is viewed.